GB879526A - Thermostatically controlled electrically-heated containers - Google Patents

Abstract

879,526. Thermal switches. BULPITT & SONS Ltd. Jan. 29, 1958 [Oct. 30, 1956], No. 33057/56. Class 38 (5). [Also in Group XI and XXXVI] An aluminium jug is provided with a heater 6 of the tubular sheath embedded element type, the heater having an aluminium outer casing which may be secured to the base of the jug by aluminium solder. The ends 9, 10 of the casing are closed by material such as silicone rubber where leads 11 leave the easing for connection to pin contacts 12, 13 between which a thermal contact and earthing pin 16 is mounted. The pin 16 is secured to a lug 17 which may be soldered to the casing of the heater. An inlet plug includes a socket 18 complementary to the pin 16, the socket projecting slightly beyond current-carrying sockets 32, 33, Fig. 3 (not shown), so that the pin will engage the socket 18 before the sockets 32, 33 engage the contacts 12, 13. Alternatively, the pin may project beyond the contacts 12, 13 to engage its socket first. The inner end of the socket 18 is flattened to provide a mounting for a thermostat contact assembly, and its other end has secured on it a hook shaped bi-metallic strip 22, the free end of which may engage an insulating heel 24 provided on a spring blade 25. An extension of an adjusting screw 31 passes through a hole in the blade 25 and engages a spring blade 26. A discharge lamp or a low voltage indicator lamp 34 and shunting resistance show when the thermostat contacts open and close. The heater may be of the immersion type and appliances for cooking are specified.